Quality-of-life-adjusted survival analysis of interferon alfa-2b adjuvant treatment of high-risk resected cutaneous melanoma: an Eastern Cooperative Oncology Group study.

Abstract

To evaluate the quality-of-life effects of adjuvant high-dose interferon alfa-2b (IFN alpha 2b) treatment of high-risk melanoma. A quality-of-life-adjusted survival analysis (Quality-Adjusted Time Without Symptoms, and Toxicity [Q-TWiST]) was applied to the Eastern Cooperative Oncology Group Trial E1684, which compared high-dose IFN alpha 2b treatment for 1 year versus observation in 280 high-risk patients. IFN alpha 2b was administered at a dosage of 20 mU/m2 intravenously daily for 5 days per week for 4 weeks, and then three times weekly at 10 mU/m2 subcutaneously for 48 weeks. After 84 months of median follow-up time, the IFN alpha 2b group gained a mean of 8.9 months without disease relapse (P = .03) and 7.0 months of overall survival (P = .07) as compared with the observation group, but had severe treatment-related toxicity for 5.8 months, on average. The IFN alpha 2b group had more quality-of-life-adjusted time than the observation group regardless of the relative valuations placed on time with toxicity (Tox) and time with relapse (Rel). This gain was significant (P < .05) for patients who consider Tox to have a high relative value and Rel to have a low relative value. In contrast, for patients who value Tox about the same as Rel, the quality-adjusted gain for IFN alpha 2b was not statistically significant. An analysis stratified according to tumor burden indicated that the benefit of IFN alpha 2b was greatest in the node-positive strata. For patients with high-risk melanoma, the clinical benefits of high-dose IFN alpha 2b can offset the toxic effects. The optimal treatment for an individual patient depends on the patient's tumor burden and preferences regarding toxicity and disease relapse.